Oleaginous preparation



Patented June 15, 1943 OLEAGINOUS PREPARATION Howard C. Black, Chicago, Ill., assignor to Industrial Patents Corporation, Chicago, 111., a

corporation of Delaware No Drawing. Application May 20, 1941, Serial No. 394,330

14 Claims.

This invention relates to the preparation of improved fatty materials and more particularly it is directed to non-aqueous fats and oils which do not foam when heated, especially during deep fat frying.

In cooking with fats and oils it has been known for some time that the oil or fat will foam and froth after heating for a substantial period. This is true of practically all fats and oils employed for this purpose whether in a natural or modified, e. g.. hydrogenated, condition.

It has long been desired to find a method for overcoming this undesirable property but up until now no solution has been described nor has there been a satisfactory explanation for its cause. An unusual feature of this phenomenon is the fact that the foaming does not take place until the oil or fat has been heated for a substantial period of time. The length of time that any oleaginous material may be used before foaming sets in has now been found to depend on several factors: principally, temperature of heating, length of time of heating, the type of oil, and the amount and type of product cooked therein.

That the material fried in the oleaginous matsrial plays a part is shown by the fact that foaming is increased when sea food, such as fish, and especially clams, are cooked in the deep fat. This might be due to the absorption of fish oil by the deep fat frying material. It is known that fish oils are generally more unsaturated than the common frying agents, and because of the presence of these unsaturated constituents in the frying oil it becomes less stable toward foaming. It has now been demonstrated that unsaturated constituents in the fatty oil are in a large part responsible for the development of foaming during heating. This may be illustrated by the following table showing the time at which bad foaming occurred with bleached cottonseed oil hy="r genatcd to varying degrees of saturation.

llil It has also been discovered that the presence of free fatty acids in the composition likewise tends to increase the tendency to foam. Other results which have been observed to occur along with the foaming are increases in the viscosity of the oil, an increase in the refractive index, and a decrease in iodine number. This change in viscosity, refractive index and iodine value indicates that some chemical transformation is taking place, probably polymerization. It has been observed that the shorter the time before foaming occurs the greater is the decrease in iodine value, the increase in refractive index, the increase in viscosity, and the free fatty acid content.

In the preparation of shortening, it is common practice to attempt to reduce the fatty acid content to a minimum, hence it is not possible to completely overcome foaming in this manner. Furthermore, it is not feasible to completely hydrogenate a shortening preparation in order to remove all unsaturation because the resulting product would be too hard, have too high a melting point, and would be substantially indigestible.

In actual practice, fresh oleaginous material is added to the batch as the oleaginous material being used is lost through absorption by the food being cooked, spattering, and/or the like. This fresh material tends to reduce the foaming slightly but not sufficiently to prevent difficulty in operation.

It has now been found possible to prepare an oleaginous composition which resists foaming when heated to high temperatures for substantial periods of time, for example in deep fat frying. This has been accomplished without sacrificing any of the other desirable properties of the non-aqueous shortening, such as low melting point, digestibility, fluidity, creaming and shortcning properties, and/or the like. This result has been attained by the incorporation of a small proportion of one or more materials. These materials have been found to be effective although they fall into three unrelated classes, of which classes other more related members do not satisfactorily function. The materials which have been found to function satisfactorily are:

1. Water-insoluble polyvalent metal (e. g, alkali earth metal) soaps of fatty acids.

2. Water-soluble surface active salts of organic oxygen-containing, non-carboxylic acids.

3. Phosphoric acids.

It is interesting to note that the water-soluble soaps, such as sodium stearate and the like, which one would normally expect to operate in view of the effectiveness of the water-insoluble soaps of the same fatty acids and of the watersoluble organic sulphonic acids, do not effectively function for the present purposes.

It is surprising and unpredictable that these unrelated substances will effectively reduce the tendency for non-aqueous fatty materials to foam, However, it has been discovered that the addition of about 0.0001% to 0.5% of alkaline earth soaps, or about 0.0001% to 1% of said surface active agents, to the non-aqueous fat at any point in its manufacture, preferably after substantial completion of the shortening, will yield a product which greatly resists any tendency to foam during extended heating. Likewise, it has been found that the washing of the oils going into the shortening, preferably before hydrogenation, if this step is included, with dilute phosphoric acid (e. g., about 5%) will retard any tendency for the shortening to foam during heating.

Another method for treating the non-aqueous fatty material with phosphoric acid for this same purpose is to add a small amount, e. g., up to about 0.01%, of concentrated phosphoric acid, e. g., 85%, to the fatty compound afte: hydrogenation in the presence of the nickel hydrogenation catalyst. Any of these methods may be employed alone or in combination to effect maximum improvement in the anti-foaming proper? ties of the deep fat frying agent.

The first class of stabilizing agents includes the water-insoluble, fat-soluble, non-toxic, polybasic metal salts of aliphatic, monobasic, carboxylic acids, such as the calcium, strontium, barium, and/or magnesium salts or soaps of stearic acid, magaric acid, palmitic acid, pentadecanoic acid, myristic acid, tridecanoic acid, lauric acid, undecanoic acid, capric acid, nonoic acid, caprylic acid, heptoic acid, caproic acid, valeric acid, butyric acid, propionic acid, acetic acid, formic acid, behenic acid, oleic acid, elaidic acid, palmitoleic acid, isoleic acid, melissic acid, carnaubic acid, undecenoic acid, elaeostearic acid, linoleic acid, linolenic acid, arachidic acid, behenolic acid, cerotic acid, ricinoleic acid, oxidized petroleum acids, naphthenic' acids, and/or abietic acid. These salts may be prepared by any suitable method, either directly from the acids or from the natural oils. fats or waxes containing them, by reaction with the oxides, hydroxides, or carbonates of the above-noted metals, or by an ion exchange reaction of salts of these metals with monobasic salts of the corresponding fatty acid or acids, such as aqueous solutions of the sodium soaps thereof.

The water-soluble, fat-soluble, non-toxic salts of organic, non-carboxylic, poly-oxygen-containing acids which may be employed in the present process include, among others, the aliphatic, cycloaliphatic, heterocyclic and aromatic sulphonates, sulphates and phosphates. Among the suitable materials of this class are the long chain aliphatic primary and secondary sulphates and sulphonates, such as sodium lauryl sulphate, tetraisobutylene sulphonate and sodium cetane hydroxy sulphonates; sulphated polyhydric alcohol partial esters, such as lauric acid monoglyceride monosulphate; sulphonated and sulphated fatty acids and their esters, such as sulphonated oleic acid and sulphated castor oil; sulphonated alkyl esters of fatty acids, such as the lauric acid ester of isethionic acid salts; sulphonated and sulphated alkyl amides of fatty acids, such as the monolaurate of taurine salts; sulphonated and sulphated polybasic acid esters, such as the di-decyl ester of sulphonated succinic acid and dioctyl ester of sulphated succinic acid sodium salt; aryl and alkylated aryl sulphonates, such as polybutylated naphthalene sulphonates, and. dodecyl benzene sulphonates; sulphonated petroleum, petroleum extracts, petroleum fractions, cracked petroleum, coal tar fractions, olefines, and the like; long chain, branched or straight, primary or secondary, aliphatic orthometa.-, or tetra-phosphates and thiophosphates; long chain fatty acid partial esters of polyhydric alcohol partial ortho-, meta-, or tetra-thiophosphates and phosphates; and various related materials. The salts of these compounds may be those of sodium, potassium, and the other alkali metals; ammonium; mono-, di-, triand tetraalkyl and alkylol ammonium; pyridinium and substituted pyridinium; calcium, barium, strontium, magnesium; and various other metals or positive radicals. The aliphatic substituents may be any having at least four carbon atoms. For example, the lauric acid radical may be substituted by any of the fatty acid radicals recited hereinbefore. The octyl, tetraisobutylene, cetyl, butyl, decyl, and dodecyl groups may be replaced by any other straight or branched chain, primary secondary, or tertiary aliphatic groups having at least four carbon atoms.

Among the materials which may be improved by the various agents and treatments disclosed in this application are lard, palm oil, olive oil, cottonseed oil, soy bean oil, coconut oil, oleo oil, lard oil, peanut oil, these oils partially hydrogenated, and various blends of these oils partially hydrogenated oils, and/or fully hydrogenated oils.

The improved fats and oils may contain other modifying agents, such as fatty acid monoglycerides and other polyhydric alcohol partial esters; alkylolamides of fatty acids; itamalic acid, citric acid, mesaconic acid, tartaric acid, citramalic acid, citraconic acid, fumaric acid, itaconic acid, and other polybasic unsaturated and/or hydroxy substituted acids; polyhydric phenols; gum guaiac and/or the like.

The following examples are given for the purpose of illustrating the present inventions but are not intended to be limiting on the scope thereof.

EXAMPLE I A blend of cottonseed oil, 15% soy bean oil, and 5% coconut oil is washed with 5% phosphoric acid in the proportion of about 10% of the blended oils with agitation for about fifteen minutes, The mixture is permitted to settle and the immiscible layers separated. The blended oils are then hydrogenated with, 0.1% Rufert catalyst at a temperature of about 360 to 385 F". and a hydrogen pressure of about thirty pounds per square inch gauge for about one hour until the refractive index at 60 C. has been reduced about four points. To this hydrogenated oil is then added 002% of phosphoric acid. After the acid is incorporated, the hydrogenated oil is filtered to remove the catalyst. This treated oil is then blended with a substantially completely hydrogenated cottonseed oil having a titre of seed oil having a refractive index of 33 at 60 (2.

about 60 C. and an iodine number of less than 3 in the proportion of 90% blended hydrogenated oil and 10% hard fat. The mixed product is then deodorized by heating to about 400 F. for five hours while blowing with a slow current of steam and maintaining the mixture under a vacuum. After the temperature has dropped to 325 F., 002% citric acid is added. Th product is run over the roll and is then tempered in a constant temperature room at 85 F. for a period of fortyeight hours. This finished product is then heated to a deep fat frying temperature of 375 F. and used for frying bread. Substantially no foaming occurs until after twenty to twenty-four hours of heating, whereas appreciable foaming occurs with similarly prepared 'shortenings which omit the phosphoric acid treatments before sixteen hours have elapsed.

Single acid treatments with phosphoric acid as by washing with the acid before hydrogenation or by adding the acid to the hydrogenated oil in the presence of the hydrogenation catalyst produce improved shortenings with respect to foam resistance but not to the extent obtained with the double acid treatment. It is important to note that the simple addition of phosphoric acid to the hydrogenated shortening after removal of the catalyst produces a product which foams more than the non-treated shortening.

The phosphoric acid which is used for washing the oleaginous material at some point in the process is preferably 5-20% aqueous phosphoric acid. It is advantageously used in the propor-.

'ticn of 1% to 20% based on the weight of the oleaginous material, but other concentrations or proport ons may be employed although less satis factory. -The acid used for treating the fatty material in the presence of the hydrogenation catalyst is concentrated phosphoric acid having a concentration of about 60% acid (1. higher and temperature of about 375 F. and small pieces of wet bread are fried therein. The following table sets forth the improved results obtained with the modified oils TABLE 11 Hours Product Untreated oil OK OK F BF VBF VBF VBF Oil+0.0l% calcium stoarate 0K 0K SF F F BF BF VHF Oil-+0.05% calcium stearate ...v 0K 0K OK OK VSF F (NH-0.1% calcium steer-eta... OK OK OK OK OK SF 1" Oil+0.05% strontium stearatd f OK OK OK VSF F F Oll+0.l% strontium;

stearate OK OK OK OK VSF SF Oil+0.0l% barium stearate OK OK SF F F BF BF Oil+0.05% barium stearate... OK OK OK SF F Bl Oil+0.l% barium v stearate i. OK OK OK OK OK I Oil+0.0l% magna slum shearer-0...... OK OK SF F F BF Oil-+01% magnesium stearatevn OK OK OK OK SF F Key: OK-No Foam F-Foam BFBad Foam VBF-Vcry Bad Foam I SF-Slight Foam VSFVery Slight Foam EXAIVIPLE HI Portions of hydrogenated cottonseed oil having a' refractive index of 38 at to C. and a free fatty acid content of 0.04% (as oleic acid) are admixed with varying proportions of sulphonated surface active agents. The treated oil and non-treated oil are heated to deep fat frying temperatures and used for frying wet bread. The following table illustrates the results obtained with such frying operations.

TABLE III Hours Product Untreated oil.. OK OK SF F F BF 3F VBF ()il+0.0l% sodium salts of hexadecyl sulphonatc and octadecyl sulphcnate(MPl) Oh Oh VSF SF F ..O 1+0.1%same OK OK. VSF VSF SF O1l+0.0l% sodium salt of dioctyi sulpho-succinate (Aerosol 0T) OK OK VSF SF SF (hl+0.l%same.... OK OK SF SF SF l1 ()il+0.l% sodium salts of long chain alkyleted naphthalene sulphonntes (Nacco nolNRSr) OK OK OK OK OK 012 OK OK 35F ()il+0.00a%same.... OK OK OK OK OK VSF "HF SF F usually is employed in the proportion of 0.00-01% to 0.01%, based on. the weight of the fatty material (preferably saturated and/or monolefinic) to be treated. Upon heating to temperatures of 300 F. or higher the products improved by the disclosed method show substantially increased resistance to foaming.

EXAMPLE It Portions of a partially hydrogenated cottonare admixed with varying percentages of calcium stearate, strontium stearate, barium stearate and magnesium stearate. The treated oils and untreated oil are then heated to a deep fat frying is EXAB/FZPLE IV and pics are determined at al tests. The results in comparison to the values of the original oil are ing a small amount of concentrated phosphoric acid to a substantially dry fatty acid glyceride in given in the following table.

TABLE IV TABLE IV H {tours E GliTOOAHt Rail-co l/Zisicosity ours e ore vo pette Product heated foam in index nEethod),

started oleic at 60 0. Bacon Original oil 0. 04 38. 26. 1 Untreated oil 65 26 0. 83 42.0 52. 9 Do 44 26 0. 73 41. 6 49. 0 Oil-H117 calcium stearatc" 55 44 40.7 40.9 Oil+0.05 a calcium stcm'atc 44 40 0 48 40. 3 38. 8 Oil-0,1 magnesium stoerntc 55 55 0. 68 39. 32.4

Oil+0.l o sodi salt alkyleted naphtholenc sulphonic acid 44 5O 0. 33 30. 6 33. 0

The data indicate. as pointed out hereinbefore, that foaming is related to the increase in free fatty acids during the heating and frying, and also to the increase in viscosity and refractive index. The increase in viscosity and refractive index indicates that polymerization is probably taking place. This is further supported by the fact that the iodine value of the deep fat frying agents decreases during heating and frying and the shorter the time before foaming occurs, the greater is the decrease in the iodine value.

It is possible to combine the various treatments to obtain especially effective results, such as the combination of the phosphoric acid treatment along with the use of the insoluble soaps, but although desirable this is not essential.

Obviously many modifications and variations of the invention hereinbeiore set forth may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

I claim:

1. A process for improving the resistance to foaming of oleaginous materials which comprises washing an oleaginous material with phosphoric acid, separating the treated oleaginous material from the aqueous acid, partially hydrogenating the pretreated oleaginous material in the presence of a nickel hydrogenation catalyst, and adding concentrated phosphoric acid to the partially hydrogenated oleaginous material in the presence of the nickel hydrogenation catalyst.

2. A process for improving the resistance to foaming of fatty acid glycerides which comprises washing a fatty acid glyceride with a substantial quantity of dilute phosphoric acid, separating the treated fatty material from the aqueous acid, partially hydrogenating the pretreated fatty material in the presence of a nickel hydrogenation catalyst, and adding a small amount of concentrated phosphoric acid to the partially hydrogenated fatty material in the presence of the nickel hydrogenation catalyst.

3. A process for improving the resistance to foaming 0f oleaginous materials which comprises adding phosphoric acid to a substantially dry oleaginous material in the presence of a nickel hydrogenation catalyst.

4. A process for improving the resistance to foaming of fatty materials which comprises adding a small amount of a phosphoric acid to a sub stantially dry fatty material in the presence of a nickel hydrogenation catalyst and thereafter separating the catalyst from th resulting product.

5. A process for improving the resistance to foaming or fatty materials which comprises addthe presence of a nickel hydrogenation catalyst and thereafter filtering the mixture to remove the catalyst.

6. A process for improving the resistance to foaming of fatty materials which comprises adding to a substantially dry fatty material phosphoric acid in the presence of a nickel hydrogenation catalyst, separating the catalyst from the mixture and thereafter heating the resulting product.

7. A process for improving the resistance to foaming of oleaginous materials which comprises adding up to about 0.01% of concentrated orthophosphoric acid to asubstantially dry oleaginous material in the presence of a nickel hydrogenation catalyst. I

8. A process for improving the resistance to foaming of fatty materials which comprises adding 0.0001% to 0.01% of concentrated orthophosphoric acid to a substantially dry fatty material in the presence of a nickel hydrogenation catalyst.

9. A process for improving the resistance to foaming of oleaginous materials which comprises washing a fatty material with a substantial quantity of a dilute phosphoric acid, separating the treated oleaginous material from the aqueous acid and then hydrogenating the resulting prodnot.

10. A process for improving the resistance to foaming of oleaginous materials which comprises washing an oleaginous material with at least 1% of dilute orthophosphoric acid and separating the treated fatty material from the aqueous acid and then hydrogenating the resulting product.

11. A process for improving the resistance to foaming of fatty materials which comprises wasln ing a fatty material with between about 1% and 20% of 5% to 20% orthophosphoric acid and senarating the treated fatty material from the aqueous acid and then hydrogcnating the resulting product.

12. In the manufacture of oleaginous material suitable for deep fat frying without substantial foaming, the steps which comprise washing an oleaginous material with a substantial quantity of dilute phosphoric acid, separating the treated oleaginous material from the aqueous acid, partially hydrogenating the pretreated oleaginous material in the presence of a nickel hydrogenation catalyst, adding a small amount of c0ncentrated phosphoric acid to the partially hydrogenated oleaginous material in the presence of the nickel hydrogenation catalyst, and heating the substantially dry oleaginous material to a temperature of at least 300 F. for a substantial period.

14. In the manufacture of fatty materials suitable for deep fat frying without substantial foaming, the steps which comprise adding a small amount of concentrated orthophosphoric acid to the fatty material in the presence of the nickel hydrogenation catalyst, separating the catalyst from the mixture and heating the resulting product to a deodorizing temperature in the presence of steam for a substantial period.

HOWARD C. BLACK. 

